I actually had an overlay on each of the four icons that were the same size and shape as the rest of my icons ! The opacity of the overlay was set to 5% (or something low enough not to be very visible) !
But I'm sure if you have the icon without any overlay in the same dimensions as all other icons (114x114 - Default iOS icons), then it should work!
The opacity of the overlay was set to 5% (or something low enough not to be very visible) !
But I'm sure if you have the icon without any overlay in the same dimensions as all other icons (114x114 - Default iOS icons), then it should work!